The present invention provides a method and apparatus for producing a treated hydrocarbon containing stream for use as a feed to a steam methane reformer of a hydrogen plant. In accordance with such method, amounts of olefins and organic sulfur species within an untreated feed are decreased in a reactor that is operated in either a hydrogenation mode to hydrogenate the olefins into saturated hydrocarbons or a pre-reforming mode in which hydrocarbon containing two or more carbon atoms including the olefins are reacted with oxygen and steam to form saturated hydrocarbons, methane, additional hydrogen and carbon monoxide. The reactor is configured and operates at a sufficiently high space velocity that olefin and organic species slip occurs that is further treated in a hydrotreater. The reactor contains a catalyst capable of promoting both hydrogenation and oxidation reactions and the hydrotreater contains a catalyst that is capable of only promoting hydrogenation reactions.